T-shirts that detect Wi-Fi signals.

When activity recognition is performed indoors and in cities using the widely available Wi-Fi signals and 802.11 access points, there is much noise and uncertainty.

A user action discovery model is presented by Yin et al., where the Wi-Fi signals are segmented to produce possible actions.

Sheet metal in walls or roofs, may efficiently reflect Wi-Fi signals, causing signal loss or multipath problems.

Although ads from companies like Intel suggest that the world is blanketed in Wi-Fi signals, Mr. Gitman said, coverage is in fact still limited.

Innovators, like Republic Wireless, are providing low-cost mobile service that relies largely on harvesting Wi-Fi signals.

Some legal experts say using stray Wi-Fi signals is like trespassing.

The game is unique, as its game play consists mainly of collecting, making use of Wi-Fi signals picked up by the handheld.

The game utilises Wi-Fi signals from the player's surroundings to "pick up" stardust and treasures.

He has come across similar situations in certain homes and apartment buildings in which Wi-Fi signals won't carry even a few yards.